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Mitika is an important representative plateau wetland in China. In order to study the spatial distribution characteristics and pollution status of heavy metals in the surface soil of the wetland, 25 surface soils were collected. The pollution of heavy metals (Cu, Zn, Cr, Ni, Pb, Cd, As and Hg) in wetland soil was evaluated by geo-accumulation index method and potential ecological risk index (RI). The results showed that the average concentrations of Cu, Cr, Ni and Pb in wetland soil in the study area were lower than the background value of Tibet soil, while the average concentrations of Zn, Cd, As and Hg are 1.11, 1.75, 1.15 and 1.53 times of the background value respectively, which was far lower than the risk screening value of GB 15618-2018 soil environmental quality standard, standard for soil pollution risk control of agricultural land (Trial); Except that the accumulation index of Cd element was 0.08, which was slightly polluted, other elements were at the pollution-free level; The potential ecological risk in the study area was moderate, which was mainly related to the accumulation of Hg in the environment and the local low background value; Cu, Zn, Cr, Ni, Pb, Cd and As were mainly from natural sources. Hg was greatly affected by human activities, which brought certain risks to the ecological environment and need to attention. However, the overall environmental quality of wetlands was better than that of other wetlands in China. [ABSTRACT FROM AUTHOR]